The Proton launcher, which has completed over 410 launches since 1965, was the European launch system Ariane's biggest competitor on the commercial market. It was developed by Vladimir Tchelomei, who inherited the German missile V-1 in 1944, carried out naval missions, and then became the principal competitor of Sergei Korolev, the founder of the Soviet space program.

This book is divided into two parts: "The Proton in the East" which relates the history of the launcher in the USSR/Russia, and "The Proton in the West" which tells the history of the commercialization of the launcher in the West thanks to the American–Russian joint venture, the International Launch Services (ILS), founded in 1995. This book incorporates the latest information unveiled by Russia.